Fuel distributing system for stokers



Sept. 1, 1931. I M, MYER 1,821,068

FUEL DISTRIBUTING SYSTEM FOR STOKERS Filed July 25. 1929 2 Sheets-Sheet l l mgr/1111101127111 ,INVENTOR 51/, yr:- 5 BY 4 A TTORNE Y Sept. 1, 1931. e. M. MYERS 1,821,068

FUEL DISTRIBUTING SYSTEM FOR STOKERS Filed July 25. 1929 2 Sheets-Sheet 2 1 13 I 1 20' 1 1 24 4 g 26 a1 M .35 z7 as" 37 36 V V' gm INVENT OR EL/Y /y m A TTORNEY Patented Sept. t, 1933 entrant series GUY M. MYERS, OF CLARENDON, VIRGINIA, ASSIGNOR TO THE STANDARD STOKER COMPANY, INCORPORATED, A C)RPORA'IJIOILJ OF DELAWARE FUEL DISTRIBUTING SYSTEM FOR STOKERS Application filed July 25, 1929.

The invention relates particularly to scatter feed types of stokers in which the fuel is distributed over the fire by a fuel distributing system including a pressure fluid blast. In stokers of this character, the fuel is carried from a source of supply to a pressure fluid blast, which of itself or in cooperation with a distributing plate or like member acts to spread the fuel over the fire. Thefuel, such as coal, supplied to the stoker varies in size from large lump to minute particles or to a finely pulverized form. When coal of this nature is delivered into the zone of a single pressure fluid blast, both the large lump and the fine fuel are subjected to a blast of the same intensity, with the result that to distribute the large lump a blast of high intensity is required and which is of excessive pressure to properly scatter the fine or powdered fuel. This action results in the building of an uneven fire bed and in the loss "of an objectionable portion of the finer particles or the pulverized fuel because the strong blast blows this diminutive fuel into the path of the swiftly moving exhaust gases, the force of which is sufficient to carry off unconsumed large quantities of the smaller particles and of the powdered fuel particularly. It is important to employ a form of distributing system which will prevent or eliminate this loss of fuel and at the same time uniformly spread the fuel over the fire.

The object of this invention is the provision of a new and improved fuel distributing system whereby the fine and the coarse fuel are separated and subjected to separate ressure fluid blasts of suitable intensity or blowing the separated fuel over the fire to efi'ect uniform distribution and to minimize the loss of unconsumed fuel.

The invention consists in the parts and the arrangement of the parts as will be hereinafter described and as illustrated in the accompanying drawings, in which Flg. 1 is a vertical section of a portion of a furnaceand a stoker therefor, showing the invention in position therein;

Fig. 2 is a detail plan section on the line 2-2 of Fig. 1;

Serial No. 380,799.

Fig. 3 is a detail vertical section on the line 3-3 of Fig. 1; and

Fig. 4 is a similar section on the line 4-4 of Fig. 1.

The invention is particularly applicable to stokers for use with locomotives and for the purpose of best illustrating the invention it will be so described, but its use is not limited to such application for it is also applicable to stokers used with other furnaces of like conditions.

The numeral 10 designates a locomotive boiler firebox backwall having a firing opening therein at 11. A suitable stoker, indicated as a whole at 12, is provided for conveying the fuel from a source of supply and delivering it to the firing opening 11. The part ofthe stoking device illustrated com.- prises a rising conduit 13 which, as is Well understood, is at the forward end of a series of conduit elements leading from a source of supply such as the tender of a locomotive. The conduit 13 is provided with a detachable hood section 14 which may be secured to the conduit in any suitable manner, and the center portion thereof comprises a door 15 hinged at its upper portion as at 16 to the hood and held closed by suitable loching means as at 17. The upper end of the conduit 13 communicates with the lower portion of the firing opening, the upper portion of the opening may be closed by the customary fire door 18. The fire door and hood section of the conduit form a closure for the firing opening. Access may be had to the firebox for hand firing, or for inspection, by opening the fire door 18 or by raising the hinged door 15, or through both.

The fuel delivered to the conduit 13 is received by a new and novel distributing system, indicated generally by the numeral 20. This means provides an arrangement for separating the fine from the coarse fuel and scattering the separated portions of fuel over the fire by separate pressure fluid blasts, as will now be described.

A riddle member or upper firing plate 21 forms a continuation of the bottom wall or fioor22 of the conduit 13. It may be made integral with the conduit, but it is preferred the lugs 25, 25a of the riddle. The apertured portion of the riddle is preferably formed ,by a separable grate member 26, which is placed in position in the riddle by disposing it on the ledge or seat 27 extending about the ends and forward side of the recess 28 provided in the riddle for permitting the application of the grate member. At the rear side of the grate member 26 the tongue 29 projects into a slot 30 of the floor 22 and forms in effect a mortise and tenon joint, preventing any tendency of the grate member '26 or of the grid as a whole to tilt upward due to the weight of the fuel passing over its forward portion. The apertures 31 in the grate member 26 can be made of any size preferred, depending upon the condition and grade of fuel being used. It is obvious that the grate member 26 may be formed as an integral part of the riddle, and with such a construction the apertures 31 would then be formed in the riddle as a whole. However. to meet the changing requirements and the different grades of fuel being used, it is preferred to meet these demands and changing conditions by providing the separable grate member which can be readily renewed or replaced by a similar member havin different size apertures. The openings 31 are downwardly so that any particle of fuel entering the opening will fall through freely without clogging.

The forward face of the riddle is provided with a plurality of jet openings 32 leading into left and right hand passages 33 and 34 respectively, each of these extending across the front side of the riddle member to their respective ends thereof to communicate with the pressure fluid supply pipes 35 and 36 rejspectively.

The fuel emerging from the conduit 13 is deposited on the riddle member 21 and is forced thereover by reason of the pressure of the advancing column of fuel. .As the fuel passes across the riddle the finer particles and the powdered coal will drop through the apertures 31 on to a distributing plate or lower firing plate 37 within the zone of action of a 37 are providedwith the pockets 41, 41a, and the abutment members 42, 42a, which serve to receive and direct a portion of the fuel to the rear corners of the firebox.

In the operation of the invention, the fuel is conveyed through the conduit 13 by any suitable conveying mechanism and is delivered onto the riddle 21. As the fuel, consisting of lumps and finer particles, passes across the riddle, a separation of the fine from the coarse fuel takes place, the finer particles and the powdered fuel dropping through the apertures 31, and the lump fuel moving forward across the plate on the pressure fluid blast issuing from the jet openings 32; and that portion of the fuel which drops through the apertures falling into the zone of action of the lower and rearward pressure fluid blast issuing from the jet openings 38 of the nozzle 39.

To effect a mixed delivery of lump and fine fuel to the rear corners of the firebox, the arrangement of the riddle member with the conduit 13 is such that the fuel rising along the side walls of the conduit passes to eachside of the apertured portion of the-riddle and is delivered directly on to the distributing plate 37, this portion of fuel falling on to the plate rearward of the zone of action of the comparatively high pressure blast issuing from the riddle. The blast issuing from the nozzle 39 will then function in cooperation with the pockets 41, 41a, together with the ribs 42, 42a, to direct this mixedportion of the fuel to the rear corners of the firebox. The greater portion of the fuel falling through the riddle into the zone of action of'the lower blastis directed over the center and side portion of the fire, the upper pressure fluid blast together with the lump coal serving to form a cover over the finer particles of fuel to prevent their being caught up by the intense draft and carried off unconsumed. Preferably, the blast issuing from the jet openings 32 of the riddle is more powerful than the lowerblast issuing from the nozzle 39, this arrangement being desired because the high pressure blast distributes the lump fuel, whereas the lower blast scatters the finer particles of fuel which do not re- (uire the same force for spreading over the Those familiar. with firing practice, of locomotives particularly, will recognize this invention provides a fuel distributing system, the parts and the arrangement of parts of which provide a very efiective means for separating the fine from the coarse fuel at the point of distribution, the lump fuel being projected by a blast issuing from a point forward of the place of separation and the diminutive fuel dropping into a blast issuing from a nozzle rearward of the place of separation and in a horizontal plane lower than that blast which projects the lump fuel over the fire. It will be recognized also that with the operation of the invention as described, that a proper mixture of the fuel is secured for effecting a'uniform mixture and distri- 5 bution of the fuel on the firebed. The separation of the fine from the coarse fuel rearward of the high pressure blast eliminates the loss of the finer particles of fuel and insures the distribution of this portion of the fuel to the I 10 fire at a point beneath thehigh pressure blast,

which then becomes a protective covering further preventing loss of the finer particles of fuel.

This invention has the further advantage of being applicable to existing stoking devices. The plate 37 and the nozzle 38 are of the form now used in practice, and it will be observed that the novel riddle member can be readily applied in the position shown in the drawings with little, if any, change being made to the existing structure. The arrangement has the further advantage of being capable of use on all classes of scatter feed types of stockers, regardless of the grade or condition of the fuel being used; for example, in locomotive service the tendency is to operate the locomotives over what is known as extended runs in which the locomotive operates over several divisions, and in all instances the supply of fuel is replenished one or more times throughout each divlsion. The grade and size of coal supplied varles considerably from one division to the other. Over one division the requirement as to smoke restrictions, may be rigid, and run-of-mine fuel consisting mostly of lumps may be used, and with such fuel it is desirable to use a distributing system in which the fine fuel is separated from the coarse to prevent smoke and stack losses and for this purpose the rlddle member 21 of this invention can be provided. The following division may be in a less populated territory and where screenings or slack coal can be supplied and used more economically than can be done by storing lump fuels. With such coal there is not the need for the riddle and it can be detached and the plate 37 and nozzle 38 used as the sole means for scattering the fuel. Thus the distributing system as provided is flexible to meet the changing demand upon the stoking device in actual service.

It will be seen that certain modifications of the invention referred to in the foregoing description and others may be used without departing from the intended scope of the invention.

I claim:

1. In a fuel distributing system for scattering fuel in aerial paths over a fire comprising a riddle and a fuel directing member beneath said riddle, said riddle having perforations to permit separation of the finefrom the coarse fuel, the fine fuel dropping through the riddle on to said directing member and the coarse fuel passing over said riddle, a nozzle beneath said riddle rearward of the perforations and adapted to issue a blast of pressure fluid across said fuel directing member, and a second blast in a plane above the first named blast forward of the point of separation of fine and coarse fuel for receiving and projecting the fuel passing over said riddle continuously over the entire firebed.

2. In a fuel distributing system for scattering fuel in aerial paths over a fire comprising a riddle provided with perforations to permit a separation of the fine from the coarse fuel, the fine fuel dropping through said riddle and the coarse fuel passing thereover, means beneath said riddle for receiving the fine fuel and means below and rearward of said riddle for projecting it over the fire, and means in a plane above said first named means forward of said riddle for receiving and continuously projecting the fuel passing over said riddle over the entire firebed.

3. In a fuel distributing system for scattering fuel in aerial paths over a fire comprising a riddle and a fueldirecting member beneath Said riddle, said riddle having perforations to permit the separation of fine from the coarse fuel, the fine fuel dropping through the riddle on to said directing member and the coarse fuel passing over said riddle, means below and rearward of said riddle for pro jecting the fuel from said directing member, and a pressure fluid blast, in a plane above said means forward of said riddle, for receiving and continuously projecting the fuel pajlssing over said riddle over the entire fire- 4. In combination with a boiler, a riddle member in said firing opening receiving the fuel from said conduit and arranged for the separation of the fine from the coarse fuel, a distributor plate in said opening beneath said riddle for receiving the fine fuel therefrom, a nozzle below and rearward of said riddle adapted to issue a blast of pressure fluid forward beneath the riddle across said distributor plate, and a second pressure fluid blast issuing in a plane above the first named blast forward of said riddle for continuously projecting the fuel passing over said riddle over the entire firebed.

5. In combination with a boiler, a stoker system comprising a conduit element terminating opposite the firing opening into the boiler, a riddle extending longitudinally forward in said opening in continuation of the floor of said conduit and arranged for the separation of the fine from the coarse fuel, a distributor plate in said opening beneath said riddle for receiving the fine fuel therefrom, a nozzle below and rearward of said riddle adapted to issue a blast of pressure fluid forward across said distributor plate and beneath the riddle, and a second pressure fluid blast issuing from said riddle forward of the place of separation of fine from the coarse fuel and being in a horizontal plane above said first named blast.

6. As a new article of manufacture, a riddle member for use in a fuel distributing system of a stoker comprising a perforated plate, a plurality of passages in said plate for the supply of pressure fluid, and a plurality of jet openings in one end of said plate connecting with said passages.

7. In a fuel distributing system, the combination of a recessed plate, a grate arranged to be received by said plate in the recessed portion thereof, a plurality of passages in the forward portion of said recessed plate for the supply of a pressure fluid, and a plurality of jet openings in the forward face of said recessed plate connecting with said passages.

8. In a fuel distributing system for scatteringfuel in aerial paths over a fire, the combination of a lower firing plate, means for projecting fuel forwardly from said plate, an upper firing plate spaced above said lower plate, means for delivering fuel to said upper plate, riddling means in said upper plate whereby fine fuel drops through said riddling means and coarse fuel passes thereover, and means on said upper plate acting on the fuel forward of said riddling means for projecting fuel forwardly therefrom.

9. In a fuel distributing system for scattering fuel in aerial paths over a fire, the combination of a lower firing plate having pressure fluid blast means at the rear thereof, an upper firing plate spaced. above said lower plate, means for delivering fuel to said upper plate, riddling means in said upper plate whereby coarsefuel is collected on said upper plate and the finesare dropped onto said lowor plate, and pressure fluid blast means on said upper plate acting on the fuel forward of said riddling means.

10. In a fuel distributing system for scattering fuel in aerial paths over a fire, the combination of a lower firing plate having pressure fluid blast means at the rear thereof, an upper firing plate spaced above said lower plate and extending forwardly at least as far as saidlower plate, means for delivering fuel to said upper plate, riddling meansin the rearward portion of said upper plate whereby fine fuel drops through said riddle and coarse fuel passes thereover, and pressure fluid blast means on said upper plate acting on the fuel forward of said riddling means.

In testimony whereof I aflix my signature.

GUY MYERS. 

